| 摘要 |
PROBLEM TO BE SOLVED: To provide an aluminous sintered compact appropriate as the material for a ceramic product needing high insulating and voltage-withstanding properties at a high temp. close to 700 deg.C and its production method. SOLUTION: The rare-earth elements RE (lanthanum, praseodymium, neodymium, etc.), are added to alumina to form the crystal phase of RE-β-alumina (REAl11O18) in a sintered compact, hence the relative density of the compact is increased to >=9%, and a high-voltage-withstanding aluminous sintered compact is obtained. The voltage-withstanding property is further improved by adjusting the Na content in the compact to <=0.05 pts.wt., expressed in terms of the oxide. The withstand voltage of the compact is kept at >=60 kV/mm, and the compact is appropriately used as an insulator for a spark plug, etc. |
